JP2000008102A - Refractory vessel for sintering titanium and titanium sintering - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a refractory vessel for sintering a powder-compacted body advantageous for the increase of the quality of the sintered body obtd. by sintering the powder-compacted body and to provide a sintering method of the powder-compacted body. SOLUTION: This refractory vessel 1 is provided with a housing chamber 10 housing a powder-compacted body 3 and is arranged in a heating furnace for sintering the compacted body 3 in a state that the compacted body 3 is housed in the housing chamber 10. A deaerating port 14 communicating the inside and outside of the housing chamber 10 is formed on the refractory vessel 1. In the case (the area of the deaerating port/the exposed area of the compacted body) is defined as α, 0.0001<=α<=0.1 is set. Moreover, a stop vave for opening and closing the deaerating port may be provided.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a refractory container for sintering powder compacts and a method for sintering powder compacts. INDUSTRIAL APPLICABILITY The present invention can be used, for example, when sintering a powder compact, such as a titanium-based powder compact, which may be affected by a substance released from a furnace wall of a heating furnace.

[0002]

2. Description of the Related Art In sintering a powder compact, a powder compact is prepared, and the powder compact is heated in a heating furnace to form a sintered compact. As a known technique in this field, a refractory container having a size that can be inserted into the furnace chamber of the heating furnace is used, and the refractory container is placed in the heating furnace while the powder compact is stored in the storage chamber of the refractory container. A technique of heating a powder compact for sintering is known (Japanese Patent Application Laid-Open No. 10-8106,
JP-A-3-267306, JP-A-57-8590
No. 2).

[0003] By the way, substances which affect the powder compact may be generated in the furnace chamber of the heating furnace. For example, depending on the type of the furnace wall of the heating furnace, the type of the atmosphere in the furnace, and the like, a gas containing carbon or oxygen that affects the powder compact may be released from the furnace wall of the heating furnace into the furnace chamber. According to the technique using the refractory container for accommodating the powder compact, even if the substance affecting the powder compact is released into a furnace chamber from a furnace wall of a heating furnace or the like, the refractory container remains in the powder compact. , The contact of the affecting substances with the powder compact can be suppressed by the refractory container,
This is advantageous for improving the quality of the sintered body.

For example, even in the case of a titanium-based powder compact which is susceptible to a gas containing carbon or oxygen generated from the furnace wall of a heating furnace, it is determined that the gas contacts the powder compact in a refractory container. Can be suppressed effectively. Therefore, the powder compact can be sintered well, which is advantageous for improving the quality of the sintered compact.

[0005]

However, according to the above technique, the powder compact is sintered in a state in which the powder compact is housed in the accommodation room of the refractory container, so that the gas discharged from the powder compact is fired. There is a possibility that the ability to discharge the state discharge substance to the outside of the powder compact may decrease. For example, wax added to the powder compact material for molding of the powder compact is subjected to a dewaxing process prior to the main sintering process.
It becomes difficult to discharge the gaseous emission generated by the dewaxing treatment to the outside of the refractory container.

In the case where the powder compact has a hydride as a main component, such as a titanium-based powder compact containing titanium hydride as a main component, if the refractory container is used, the powder is discharged from the powder compact. It becomes difficult to discharge the discharged hydrogen gas to the outside of the refractory container. For this reason, the technique of sintering using a refractory container that accommodates the powder compact is advantageous in improving the quality of the sintered compact, but has limitations.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned circumstances, and a refractory container for sintering a powder compact, which is advantageous for improving the quality of a sintered compact obtained by sintering the powder compact, and a powder compact. It is a common object to provide a method for sintering.

[0008]

Means for Solving the Problems The present inventor has proceeded with the development to achieve the above-mentioned object. We have developed a refractory container that has a deaeration port that connects the inside and outside of the storage room. However, if the deaeration port area is not appropriate, substances released from the furnace wall of the heating furnace or the like excessively contact the powder compact in the refractory container and affect the sintering of the powder compact, Alternatively, the gaseous emission material discharged from the powder compact cannot be satisfactorily discharged to the outside of the refractory container, resulting in a disadvantage that the sintering of the powder compact is affected.

The present inventor studied the relationship between the area of the deaeration port and the exposed area of the powder compact, and found that (area of the deaeration port /
When the surface area of the powder compact is α, 0.0001
If set to ≦ α ≦ 0.1, the gas discharged from the powder compact while suppressing excessive release of the substance released from the furnace wall of the heating furnace or the like to the powder compact in the refractory container It has been found that the exhaust gas can be effectively discharged to the outside of the refractory container and that the powder compact can be sintered well, and confirmed by a test. Thus, the first invention and the second invention have been completed.

The inventor of the present invention has also formed a vent valve communicating with the inside and outside of a storage chamber in a refractory container, closing the vent port and opening the vent port as the pressure in the storage chamber increases. Is provided, it is possible to effectively prevent gaseous emission substances discharged from the powder compact while suppressing excessive contact of the substance generated from the furnace wall of the heating furnace with the powder compact in the refractory container. It has been found that the powder compact can be discharged and that the sintering of the powder compact can be favorably performed, thereby completing the third invention.

That is, the refractory container for sintering a powder compact according to the first invention includes a storage chamber for accommodating the powder compact, and sintering the powder compact in a state where the powder compact is stored in the storage chamber. In the refractory container for sintering the powder compact, which is disposed in the heating furnace for the purpose, a deaeration port communicating between the inside and the outside of the storage chamber is formed, and (area of the deaeration port / exposed area of the powder compact) )
When α is α, it is set that 0.0001 ≦ α ≦ 0.1.

A method for sintering a powder compact according to a second aspect of the present invention comprises:
In a method of sintering a powder compact including a step of preparing a powder compact and a heating step of heating the powder compact in a heating furnace for sintering, in the heating step, (aeration opening area / powder compaction) 0.0001 ≦ when the surface area of the body) is α
Using a refractory container provided with a deaeration port set to α ≦ 0.1, and sintering the powder compact in a state where the powder compact is stored in the storage chamber of the refractory container. is there.

According to a third aspect of the present invention, there is provided a refractory container for sintering a powder compact, comprising a storage chamber for accommodating the powder compact, for sintering the powder compact in a state where the powder compact is accommodated in the storage chamber. In the refractory container for sintering the powder compact disposed in the heating furnace, a deaeration port communicating with the inside and outside of the storage chamber is formed, and the deaeration port is closed and deaeration is performed as the pressure in the storage chamber increases. It is characterized in that a closing valve for opening a vent is provided.

[0014]

BEST MODE FOR CARRYING OUT THE INVENTION The refractory container according to the first to third aspects of the present invention has a storage chamber for storing a powder compact. The material of the refractory container is preferably one having heat resistance and durability. For example, a carbon material and a ceramic material can be used, and in some cases, a metal material having heat resistance can be used. Examples of the carbon material include graphite and glassy carbon. Further, as the ceramic material, for example, ZrO ₂ , MgO, A
oxide ceramics such as l ₂ O ₃ , SiO ₂ , BeO, TiO ₂ , boride ceramics such as ZrB ₂ , FeB, carbide ceramics such as ZrC, Tac, SiC, TiC, BN, TaN, AlN, Si ₃ N ₄ nitride ceramics or the like can adopted.

The refractory container is preferably formed of a material having a low porosity and a high density in order to enhance the protection of the powder compact. Therefore, the porosity of the refractory container is, for example, 0
It is preferably from 40% to 40%, particularly preferably from 0% to 20%. The refractory container may have a single structure or a multiple structure. The refractory container according to the first to third inventions is provided with a deaeration port. The shape of the deaeration port is not particularly limited, and a triangular shape, a circular shape, a square shape, or the like can be employed.

According to the refractory container according to the first and second aspects of the present invention, when (aeration area / exposed area of powder compact) is α, 0.0001 ≦ α ≦ 0.1 is set. Have been.
Although the upper limit and the lower limit of α differ depending on the composition of the powder compact, the gaseous emission substance generated from the powder compact, and the like, the upper limit is, for example, 0.08, 0.0
6, 0.04, 0.02, 0.01 can be appropriately adopted.
For example, 0.0002 can be adopted as the lower limit.

The exposed area of the powder compact means an area where the powder compact is exposed to the accommodation room of the refractory container. Since the bottom surface of the powder compact is placed on the refractory container, when the bottom surface of the powder compact is not exposed to the accommodation room of the refractory container, the exposed area of the powder compact for setting α is Excluding the area of the bottom surface of the powder compact. According to the method for sintering a powder compact according to the second invention, a step of preparing the powder compact and a heating step of heating the powder compact in a heating furnace for sintering are performed. The powder compact is formed by molding a powder aggregate mainly composed of a metal powder or a ceramic powder. For example, a green compact obtained by compression-molding the powder aggregate can be employed.

As the powder, titanium-based, iron-based, chromium-based, aluminum-based, tungsten-based, and mordendene-based powders can be employed, but are not limited thereto. As a typical powder compact, a titanium-based powder compact can be adopted,
A tungsten-based powder compact or a molybdenum-based powder compact may be used. Generally, the powder compact has at least one of the following forms. That is, a form in which a wax that can function as a lubricant for ensuring the smoothness of molding and the like is contained in the powder compact, and a binder such as an organic binder that enhances binding of powder particles is contained in the powder compact. There is a form and a form in which moisture adheres to the powder compact.

The wax, binder, moisture, etc. are discharged as a gaseous emission substance to the outside of the powder compact with heating. As the wax, for example, stearic acid, amide wax and the like can be adopted. As the binder, for example, polyethylene, polypropylene, or the like can be used. According to the first invention and the second invention, α relating to the opening area of the deaeration port
The powder compact is protected by the refractory container set in the above range. Therefore, even if a substance that affects the powder compact (for example, a substance containing carbon or oxygen that induces carbonization or oxidation) is released from the furnace wall of the heating furnace, the substance may be discharged through the degassing port. Excessive entry into the container chamber can be restricted. This can prevent the substance from excessively contacting the powder compact in the storage chamber.

Further, since α relating to the opening area of the deaeration port is set in the above range, the gaseous emission material discharged from the powder compact into the accommodation room of the refractory container due to the heating during sintering, This is advantageous for exhausting the refractory container from the deaeration port to the outside. In the heating step according to the second invention, the refractory container is placed in a heating furnace while the powder compact is housed in the refractory container. The powder compact in the refractory container is heated by a heating furnace with a predetermined heat history. At the time of heating, the surroundings of the refractory container can be, for example, a vacuum atmosphere or a non-oxidizing atmosphere. The vacuum atmosphere can be, for example, 10 ⁻² to 10 ⁻⁸ Torr, but is not limited to this.

When the powder compact is a titanium-based powder compact, the heat history at the time of heating includes the type of powder, wax,
Although it differs depending on the size of the powder compact, a process of discharging wax and the like contained in the powder compact (for example,
A dehydrogenation treatment (e.g., at 300 to 600 ° C. for 30 minutes to 4 hours) for the titanium hydride powder constituting the powder compact.
Sintering treatment (for example, at 800 to 1100 ° C. for 30 minutes to 3 hours)
Minutes to 10 hours). However, the heating temperature and the heating time relating to the heat history are, of course, not limited thereto. As the heating furnace, a structure having a furnace wall of a carbon material or the like can be adopted.

According to the refractory container according to the third aspect of the present invention, the air vent opening communicating between the inside and the outside of the accommodation chamber is formed,
A closing valve for closing the deaeration port is provided. Therefore, even if a substance that affects the powder compact (for example, a substance containing carbon or oxygen that induces carbonization or oxidation) is released from the furnace wall of the heating furnace, the closing valve closes the deaeration port. In this state, the powder compact is protected by the refractory container, that is, since the powder compact is substantially isolated from the furnace chamber atmosphere by the refractory container, the furnace affecting the powder compact is Excessive entry of the substance in the room into the accommodation room from the vent of the refractory container can be restricted. Therefore, it is advantageous to suppress the substance which affects the powder compact from excessively contacting the powder compact in the accommodation room of the refractory container.

Further, as the pressure in the storage chamber of the refractory container increases, the closing valve opens the deaeration port, so that the gaseous emission material discharged from the powder compact into the storage chamber due to heating during sintering. This is advantageous for discharging to the outside of the refractory container.
Since the weight of the closing valve affects the opening timing of the closing valve, it is preferable to select the weight in consideration of the degree of emission of gaseous emission substances released from the powder compact. The closing valve may be configured to have a cavity or may be formed of a material having micropores for weight reduction. According to the refractory container according to the third invention, α is not limited to the above range.

[0024]

Embodiments of the present invention will be described below with reference to the drawings. Embodiment 1 Embodiment 1 is shown in FIG. As shown in FIG. 1, a refractory container 1 according to the present embodiment includes a container body 11 having a bottomed shape formed of a carbon material and having a storage chamber 10 for storing a powder compact 3, and a container body 11. And a lid 12 made of a carbon material that is detachably attached to the cover. The container body 11 and the lid 12 have micropores therein, have a density of about 80 to 90%, and have a porosity of 20 to 10%.
%. The refractory container 1 having micropores is
It has the advantage of easily absorbing thermal expansion and the like. At the bottom of the container body 11, a fire-resistant plate, that is, a zirconia plate 13, which is less likely to react with the powder compact 3 is arranged.

On the side wall of the container body 11 of the refractory container 1, a degassing opening 14 of a normally open type is formed. In the present embodiment, (the area of the deaeration port / the exposed area of the powder compact 3)
Is set to α, 0.0001 ≦ α ≦ 0.1 is set. In the present embodiment, as shown in FIG. 1, since the bottom surface 3 c of the powder compact 3 is placed on the zirconia plate 13 of the refractory container 1, the top surface 3 a and the side surface 3 b of the powder compact 3
Are exposed in the accommodation room 10 of the refractory container 1, but the bottom surface 3 c of the powder molded body 3 is not exposed in the accommodation room 10 of the refractory container 1. Therefore, the exposed area of the powder compact 3 with respect to α that sets the opening area of the deaeration port 14 does not include the area of the bottom surface 3c of the powder compact 3.

The powder compact 3 according to the present embodiment is a titanium-based powder compact having a cylindrical shape, and is a green compact obtained by compression-molding a material containing titanium hydride powder (TiH ₂ powder) as a main component in a molding die. It is. Then, with the lid 12 opened,
As shown in FIG. 1, the zirconia plate 13 in the refractory container 1
A suitable number of powder compacts 3 are placed on the plate. In this case, the powder compacts 3 are not horizontal, and the plurality of powder compacts 3 are arranged side by side vertically so that the bottom surface 3 c having a small surface area of the powder compacts 3 is placed on the zirconia plate 13. ing. With this vertical arrangement, the exposed area of the powder compact 3 from which wax, hydrogen gas, and the like can be discharged is secured. In addition, the adjacent powder compacts 3 are arranged at predetermined intervals.

Thereafter, the lid 12 is attached to the container body 11 of the refractory container 1. Thus, the accommodation room 1 of the refractory container 1
The refractory container 1 is placed in the furnace chamber 5 k of the heating furnace 5 in a state where the plurality of powder compacts 3 are stored in the furnace 0. The heating furnace 5 has a furnace wall 5c formed of a carbon material and a carbon-based heating element 5d. While maintaining the furnace chamber 5k of the heating furnace 5 in a high vacuum or a medium vacuum state (10 ^-4 to 10 ^-5 Torr) by a vacuum system (not shown), the heating element 5d of the heating furnace 5 causes the inside of the refractory container 1 to be heated. The powder compact 3 is heated by the heating furnace 5 with a predetermined heat history.

In the present embodiment, the thermal history includes a dewaxing treatment for discharging the wax contained in the powder compact 3 (at 500 ° C. for 2 hours) and a dehydrogenating treatment for the titanium hydride powder constituting the powder compact 3 (1000). C. for 1 hour), a sintering process (4 hours at 1300.degree. C.), which means main sintering, and a cooling process after sintering are performed continuously. Thereby, a sintered body is obtained. By the way, as described above, during the heating for sintering, the gas containing oxygen, carbon, or the like that oxidizes or carbonizes the powder compact 3 and affects the powder compact 3 is supplied to the heating furnace. 5 may occur from the furnace wall 5c.

According to this embodiment, the powder compact 3 is covered and protected by the refractory container 1 during heating for sintering.
0.0001 ≦ α ≦ 0.1 is set. Therefore, it is possible to suppress a gas containing carbon, oxygen, and the like discharged from the furnace wall 5 c of the heating furnace 5 from excessively entering the storage room 10 of the refractory container 1. As a result, the gas is stored in the accommodation room 10.
Excessive contact with the powder compact 3 in the inside can be suppressed.
Therefore, it is advantageous to prevent the powder compact 3 in the storage chamber 10 of the refractory container 1 from being contaminated (oxidized or carbonized) by a gas containing carbon, oxygen, or the like. Therefore, it is advantageous for improving the quality of the sintered body.

In addition, during the heating for sintering, the wax component is discharged from the powder compact 3 into the storage chamber 10 as a gaseous discharge substance in the dewaxing process. In the dehydrogenation treatment, hydrogen gas is supplied from the powder compact 3 containing titanium hydride powder as a main component as a gaseous emission material to the storage chamber 10.
Is discharged into When the powder compact 3 contains moisture, the gas due to the moisture is also discharged into the storage chamber 10 as a gaseous emission substance.

In this respect, according to the present embodiment, since the deaeration port 14 is formed in the refractory container 1, the above-mentioned gaseous emission materials such as the wax component and hydrogen gas are supplied to the outside of the refractory container 1. It is advantageous for discharging. In particular, according to this embodiment,
As shown in a test example described later, α relating to the deaeration port 14 is set in the above-described range, so that gas entering the storage chamber 10 from the deaeration port 14 and the storage chamber 10
Balance with the gas discharged from the fuel cell. Therefore, the gas containing carbon, oxygen, and the like discharged from the furnace wall 5c of the heating furnace 5 is prevented from excessively entering the storage room 10 of the refractory container 1 while the gas from the powder compact 3 is inserted into the storage room 10. This is advantageous for effectively discharging the discharged gaseous substances such as the wax component and the hydrogen gas to the outside of the refractory container 1.

(Embodiment 2) FIG. 2 shows Embodiment 2. The configuration of the second embodiment is basically the same as that of the first embodiment, and basically the same operation and effect can be obtained. The refractory container 1 according to the second embodiment includes a container body 11 and a lid 12. The outer edge of the lid 12 has a facing wall 12m facing the deaeration port 14.
Are formed. The facing wall 12m covers the deaeration port 14 at a predetermined interval. Thereby, the furnace wall 5 of the heating furnace 5
It is possible to effectively suppress the gas released from c into the furnace chamber 5k from directly entering the storage chamber 10 of the refractory container 1.

Accordingly, while effectively discharging gaseous substances such as wax components and hydrogen gas discharged from the powder compact 3 in the storage chamber 10 to the outside of the refractory container 1, the storage of the refractory container 1 is performed. Powder compact 3 sintered in chamber 10
Pollution can be effectively prevented. (Embodiment 3) Embodiment 3 is shown in FIG. The configuration of the third embodiment is basically the same as that of the first embodiment, and basically the same operation and effect can be obtained. The refractory container 1 according to the third embodiment includes a storage chamber 10 that stores the powder compact 3. The refractory container 1 includes a bottom plate 16 made of a carbon material on which a zirconia plate 13 is placed, and a container body 11 made of a carbon material adhered to the bottom plate 16. Container body 11
Has a double structure, and the outer container body 11a arranged outside
And an inner container main body 11c arranged inside the outer container main body 11 with a gap 11b therebetween.

The accommodation chamber 10 is provided on the side wall of the outer container body 11a.
Are formed with a plurality of outer deaeration ports 14a for communicating the inside and the outside. In the side wall of the inner container body 11, a plurality of inner deaeration ports 14b for communicating the inside and the outside of the accommodation chamber 10 are formed. The outer deaeration port 14a and the inner deaeration port 14b are formed alternately so as not to face each other. Accordingly, it is possible to effectively suppress the gas in the furnace chamber 5k discharged from the furnace wall 5c of the heating furnace 5 from directly entering the storage chamber 10 of the refractory container 1.

(Embodiment 4) Embodiment 4 is shown in FIG. The refractory container 1 according to the fourth embodiment includes a storage chamber 10 that stores the powder compact 3. The refractory container 1 includes a bottom plate 16 on which a zirconia plate 13 is detachably mounted, and a bottom-open box-shaped container body 11 detachably attached to the bottom plate 16. A plurality of deaeration ports 14 are formed in the upper wall 11u of the container body 11. The inner wall surface 14e that defines the deaeration port 14 is reduced in diameter as it goes downward, and has a substantially conical shape. Each vent 14
Is mounted with a pressure-responsive spherical closing valve 18.

The closing valve 18 is made of a carbon material (density: 85%, porosity: 15%). The closing valve 18 is held in the deaeration port 14 in a normal state under the influence of gravity, and closes the deaeration port 14. However, when the gaseous emission released from the powder compact 3 increases and the pressure in the storage chamber 10 of the refractory container 1 increases, the closing valve 18 floats and opens, so that the deaeration port 14 is automatically opened. Is open to the public. Therefore,
The gaseous substance discharged from the powder compact 3 into the storage chamber 10 is discharged from the deaeration port 14 to the outside of the refractory container 1 and depressurized. When the accommodation chamber 10 of the refractory container 1 is depressurized in this way, the closing valve 18 automatically closes the deaeration port 14 by gravity. The closing valve 1 opposing the internal pressure of the accommodation chamber 10
The valve opening timing of the closing valve 18 can be adjusted by adjusting the weight of the valve 8.

According to the present embodiment, when (area of deaeration port / exposed area of powder compact) is α, α can be set to 0.0001 or more. Further, similarly to the first embodiment,
Although it can be set to 0.0001 ≦ α ≦ 0.1,
It is not limited to this. Fifth Embodiment FIG. 5 shows a fifth embodiment. The configuration of the fifth embodiment is basically the same as that of the fourth embodiment, and basically the same operation and effect can be obtained. Also in Example 5, the refractory container 1
A pressure-responsive spherical closing valve 18 is mounted on each of the deaeration ports 14 formed in the upper surface wall 11u. A valve holder 18k is provided in the refractory container 1 in order to prevent the closing valve 18 from dropping off while ensuring the opening operation of the closing valve 18.

The shut-off valve 18 shown in FIG.
5% and a porosity of 15%), have a cavity 18e, and are lightweight. The opening timing of the closing valve 18 can be adjusted according to the weight reduction. Accordingly, the lightened closing valve 18 easily floats early with an increase in the pressure of the storage chamber 10, and the deaeration port 14 is opened early. Therefore,
The gaseous substances in the storage chamber 10 discharged from the powder compact 3 are efficiently discharged from the deaeration port 14. When the accommodation chamber 10 of the refractory container 1 is depressurized in this way, the closing valve 18 automatically closes the deaeration port 14 by gravity.

Embodiment 6 Embodiment 6 is shown in FIG. The sixth embodiment has basically the same configuration as the fourth embodiment shown in FIG. 4, and basically has the same operation and effect. The refractory container 1 according to the sixth embodiment has a housing chamber 1 for housing the powder compact 3.
0 is provided. That is, the refractory container 1 has a bottom plate 16 formed of a carbon material on which the zirconia plate 13 is placed, and a box-shaped container body formed of the carbon material formed on the bottom plate 16 and forming the storage chamber 10. 11 is provided. The upper wall 11u of the container body 11 has a plurality of deaeration ports 14 communicating between the inside and the outside of the storage chamber 10. A pressure-responsive closing valve 18 is mounted on each deaeration port 14.

The closing valve 18 has an outer diameter larger than the diameter of the degassing port 14 and covers the valve part 18c covering the degassing port 14, and a shaft having an outer diameter smaller than the diameter of the degassing port 14. It has a part 18d. A gap 18e is formed between the outer wall surface of the shaft 18d and the inner wall surface of the deaeration port 14. The closing valve 18 closes the deaeration port 14 in a normal state under the influence of gravity. When the pressure in the accommodation chamber 10 increases, the closing valve 1
8 rises, so that the deaeration port 14 is opened. When the deaeration port 14 is opened in this way, gaseous substances discharged from the powder compact 3 into the storage chamber 10 are discharged from the deaeration port 14 to the furnace chamber 5.
It is discharged to k and depressurized. When the accommodation chamber 10 of the refractory container 1 is depressurized in this way, the closing valve 18 automatically closes the deaeration port 14 by gravity.

(Test Example) A test example A1 was carried out based on the above-mentioned Example 1. The refractory container 1 is formed of a carbon material into a cylindrical shape, has a porosity of 15%, a height of 60 mm,
The inner diameter was 200 mm. Deaeration port 14 is 3m on a side
m is a triangular shape (abbreviated as $ 3).
Were formed in one refractory container 1. In this case, α is 0.000220, and 0.0001 ≦ α
The relationship of ≦ 0.1 was satisfied.

In Test Example A1, a titanium-based powder compact was used as a test piece. The titanium-based powder compact is a green compact obtained by using a mixed material obtained by mixing a wax with a raw material powder containing titanium hydride powder (TiH ₂ powder) as a main component, and compressing the mixed material with a molding die. The titanium-based powder compact becomes a titanium-based sintered body by sintering. The amounts of oxygen and carbon contained in the titanium-based sintered body were measured, and are shown in Table 1. As shown in Table 1, in Test Example A1 according to the present invention, the amount of oxygen contained in the titanium-based sintered body was 0.30% by weight, and the amount of carbon was 0.055% by weight. Was. As described above, in Test Example A1, the amounts of oxygen and carbon contained in the titanium-based sintered body were considerably small.

As Comparative Example A1, similarly to Test Example A1, a titanium-based powder compact was used as a test piece, and was sintered in the furnace chamber 5k of the heating furnace 5 without using the refractory container 1. In the case of Comparative Example A1, as shown in Table 1, the amount of oxygen contained in the titanium-based sintered body after sintering was 0.7% by weight.
And the carbon content was as high as 0.16% by weight. This means that the gas containing carbon and oxygen generated from the furnace wall 5c of the heating furnace 5 excessively contacted the powder compact during sintering.

Further, as Comparative Example B1, a refractory container having two equilateral triangular (abbreviated as # 2) vent holes 14 each having a side of 2 mm was used, and the same heating conditions were used as in Test Example A1. Each of the titanium-based powder compacts was sintered in the heating furnace 5. In Comparative Example B1, α was 0.0000 because the opening area of the deaeration port 14 was smaller than the exposed area of the powder compact.
49, which did not satisfy the relationship of 0.0001 ≦ α ≦ 0.1 according to the present invention. In Comparative Example B1, since the lid 12 was scattered during the sintering heating, the furnace wall 5 of the heating furnace 5 was heated.
The gas containing carbon and oxygen generated from c. excessively contacts the titanium-based powder compact, and as a result, as shown in Table 1, in Comparative Example B1, the weight ratio of the sintered titanium-based compact was Has a high oxygen content of 0.38% and a carbon content of 0.13%
And many.

Further, as Comparative Example C1, a refractory container having four equilateral triangular deaeration ports 14 each having a side of 2 mm was used, and a titanium-based powder compact was heated in a heating furnace 5 under the same heating conditions.
Sintered within. In this case, since the opening area of the deaeration port 14 is smaller than the exposed area of the titanium-based powder compact,
α is 0.000098, and 0.0001 ≦ α ≦ 0.
The relationship of 1 was not satisfied. Such Comparative Example C
In No. 1, since the lid 12 was scattered during the sintering heating,
As shown in Table 1, in the titanium-based sintered body after sintering, the oxygen content was as large as 0.42% by weight and the carbon content was 0.14%.
And many.

[0046]

[Table 1] Furthermore, using a titanium-based powder compact having another composition as a test piece, under the same conditions as described above, Test Example A2 and Comparative Example A
2, Comparative Example B2 and Comparative Example C2 were performed. Test Example A2 corresponds to Test Example A1, and α is 0.000220.
It is. Comparative Example A2 corresponds to Comparative Example A1 and was sintered without using a refractory container. Comparative Example B2 corresponds to Comparative Example B1, and α is 0.000049.
It is. Comparative Example C2 corresponds to Comparative Example C1, and α is 0.000098.

The titanium-based powder compact is a green compact obtained by compression-molding a mixed material obtained by mixing a wax with a raw material powder mainly composed of titanium hydride powder (TiH ₂ powder). The composition differs from that of the base powder compact. The titanium-based powder compact becomes a titanium-based sintered body by sintering. Table 2 shows the test results. As shown in Table 2, in Test Example A2, the amount of oxygen contained in the titanium-based sintered body was as small as 0.22% by weight, and the amount of carbon was as small as 0.02% by weight. As described above, the oxygen content and the carbon content in Test Example A2 are small because the gas containing carbon and oxygen generated from the furnace wall 5c of the heating furnace 5 during sintering is formed by the titanium-based powder compact in the storage chamber 10. Means that the contact with the substrate was suppressed.

As shown in Table 2, in Comparative Example A2,
The amount of oxygen contained in the titanium-based sintered body after sintering was as large as 0.8% by weight, and the amount of carbon was as large as 0.15% by weight. This means that the gas containing carbon and oxygen generated from the furnace wall 5c of the heating furnace 5 excessively contacted the powder compact during sintering.

In Comparative Example B2, the amount of oxygen contained in the titanium-based sintered body was 0.52% by weight, and the amount of carbon was 0.14% by weight. In Comparative Example C2, the amount of oxygen contained in the titanium-based sintered body was 0.48 by weight.
% And the carbon content was 0.13% by weight.

[0050]

[Table 2] Further, using a plurality of refractory containers 1 in which the value of α was changed in the range of about 0.0001 to 0.1 to 1, under the same conditions as in Example 1, titanium-based powder molding was performed. The body was sintered in the heating furnace 5 to obtain a titanium-based sintered body. Similarly, the titanium-based powder compact was sintered in the heating furnace 5 to obtain a titanium-based sintered body. The oxygen content and carbon content were measured for each. FIG. 7 shows the measurement results of the oxygen amount. FIG. 8 shows the measurement results of the carbon content.

As can be understood from FIG. 7, α is 0.00
When it was set in the range of 01 to 0.1, the amount of oxygen in the sintered body was significantly reduced, and a critical significance was exhibited. Therefore, if α is 0.1 or less, it is advantageous to reduce the oxygen content of the titanium-based sintered body. When α is less than 0.0001, the area of the deaeration port is too small, the lid 12 is scattered, and the atmosphere in the furnace chamber directly contacts the powder compact in the refractory container, so that the oxygen amount increases. did. Even when α exceeded 0.1, the amount of oxygen increased considerably in both titanium-based sintered bodies.

As shown in FIG. 7, the amount of oxygen is particularly preferably equal to or less than the W1 line for the titanium-based sintered body, and particularly preferably equal to or less than the W2 line for the titanium-based sintered body. In consideration of these matters, α is set to 0.06 or less, 0.03
You can: As can be understood from FIG.
When it is set in the range of 001 to 0.1, the amount of carbon in the titanium-based sintered body is greatly reduced, and a critical significance is exhibited. Therefore, when α is 0.1 or less, it is advantageous to reduce the carbon content of the titanium-based sintered body. α is 0.0001
If it is less than 1, the area of the deaeration port was too small, and the lid 12 was scattered, so that the atmosphere in the furnace chamber was in direct contact with the powder compact in the refractory container, so that the carbon amount increased. If α exceeds 0.1, the area of the deaeration port is excessive,
The carbon content of both titanium-based sintered bodies increased considerably.

As shown in FIG. 8, it is particularly preferable that the amount of carbon is not more than the W3 line in a titanium-based sintered body. Taking these matters into account, α can be set to 0.03 or less and 0.02 or less.

[0054]

According to the refractory container according to the first invention and the method according to the second invention, α is set to an appropriate value when (aeration opening area / exposed area of the powder compact) is α. are doing. Therefore, while suppressing the substances released from the furnace wall of the heating furnace from entering the storage chamber of the refractory container, the gaseous emission substances discharged from the powder compact due to heating during sintering are reduced. This is advantageous for discharging to the outside of the device. Therefore, the powder compact in the accommodation room of the refractory container can be sintered well, which is advantageous for improving the quality of the sintered compact.

According to the refractory container according to the third aspect of the present invention, there is provided a closing valve for closing a deaeration port communicating between the inside and the outside of the accommodation room. Therefore, it is possible to suppress the substance generated from the furnace wall of the heating furnace or the like from entering the accommodation room of the refractory container by the closing operation of the closing valve. In addition, when the gaseous emission discharged from the powder compact into the storage chamber increases due to heating during sintering, the closing valve performs a valve opening action, so that the gas is discharged from the powder compact into the storage chamber of the refractory container. This is advantageous for discharging gaseous emission materials outside the refractory container. Therefore, the powder compact in the accommodation room of the refractory container can be sintered well, which is advantageous for improving the quality of the sintered compact.

[Brief description of the drawings]

FIG. 1 is a configuration diagram according to a first embodiment.

FIG. 2 is a configuration diagram according to a second embodiment.

FIG. 3 is a configuration diagram according to a third embodiment.

FIG. 4 is a configuration diagram according to a fourth embodiment.

FIG. 5 is a configuration diagram according to a fifth embodiment.

FIG. 6 is a configuration diagram according to a sixth embodiment.

FIG. 7 is a graph showing the relationship between the amount of oxygen in a sintered body and α.

FIG. 8 is a graph showing the relationship between the amount of oxygen in a sintered body and α. .

[Explanation of symbols]

In the figure, 1 is a refractory container, 10 is a storage room, 14 is a vent,
Reference numeral 18 denotes a closing valve, 3 denotes a powder compact, 5 denotes a heating furnace, and 5c denotes a furnace wall.

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[Procedure amendment]

[Submission Date] September 6, 1999 (September 9, 1999)

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] Name of invention

[Correction method] Change

[Correction contents]

[Title of Invention] refractory container and sintered titanium methods for sintered titanium

[Procedure amendment 2]

[Document name to be amended] Statement

[Correction target item name] Claims

[Correction method] Change

[Correction contents]

[Claims]

[Procedure amendment 3]

[Document name to be amended] Statement

[Correction target item name] 0001

[Correction method] Change

[Correction contents]

[0001]

The present invention is refractory container for sintered titanium BACKGROUND OF THE INVENTION, and to a sintered titanium methods. The present invention can utilize titanium-based powder compact that may be affected by substances released from the furnace wall of the pressurized <br/> heat furnace during sintering.

[Procedure amendment 4]

[Document name to be amended] Statement

[Correction target item name] 0007

[Correction method] Change

[Correction contents]

The present invention has been made in view of the above-mentioned circumstances, and a refractory container for sintering titanium , which is advantageous for improving the quality of a sintered body obtained by sintering a titanium-based powder compact, and a titanium sintering method. It is a common task to provide a method.

[Procedure amendment 5]

[Document name to be amended] Statement

[Correction target item name] 0008

[Correction method] Change

[Correction contents]

[0008]

Means for Solving the Problems The present inventor has proceeded with the development to achieve the above-mentioned object. We have developed a refractory container that has a deaeration port that connects the inside and outside of the storage room. However, if the area of the deaeration port is not appropriate, substances released from the furnace wall of the heating furnace, etc., will excessively contact the titanium-based powder compact (hereinafter sometimes simply referred to as powder compact) in the refractory container. Affecting the sintering of titanium-based powder compacts,
Alternatively, can not be satisfactorily discharged gaseous emissions discharged from a titanium-based powder compact to the outside of the refractory vessel, titanium
Inconveniences such as affecting the sintering of the system powder compact are caused.

[Procedure amendment 6]

[Document name to be amended] Statement

[Correction target item name] 0009

[Correction method] Change

[Correction contents]

The present inventor has studied the relationship between the area of the degassing opening and the exposed area of the titanium-based powder compact, and as a result, (the area of the deaerated port / exposed area of the titanium-based powder compact) was defined as α. At this time, if 0.0001 ≦ α ≦ 0.1 is set, it is possible to prevent the substance released from the furnace wall of the heating furnace from excessively contacting the titanium-based powder compact in the refractory container. While titanium
The gaseous effluent quality discharged from the system powder compact can be effectively discharged to the outside of the refractory vessel, thereby finding that can be favorably sintered titanium-based powder compact was confirmed by tests, first The invention and the second invention have been completed.

[Procedure amendment 7]

[Document name to be amended] Statement

[Correction target item name] 0010

[Correction method] Change

[Correction contents]

The inventor of the present invention has also formed a vent valve communicating with the inside and outside of a storage chamber in a refractory container, closing the vent port and opening the vent port as the pressure in the storage chamber increases. The gaseous emission material discharged from the titanium-based powder compact while suppressing excessive contact of the substance generated from the furnace wall of the heating furnace with the titanium-based powder compact in the refractory container. Have been found to be able to be effectively discharged, whereby the titanium-based powder compact can be favorably sintered, and the third invention has been completed.

[Procedure amendment 8]

[Document name to be amended] Statement

[Correction target item name] 0011

[Correction method] Change

[Correction contents]

That is, the refractory container for titanium sintering according to the first aspect of the present invention is a refractory container for discharging a gaseous emission material with heating.
Tan-based powder compact (hereinafter simply referred to as powder compact)
Includes a storage chamber to store a certain), in fireproof container for titanium sintered arranged in a furnace for sintering the titanium-based powder compact in a state of being housed in the housing chamber titanium-based powder compact, A deaeration port communicating the inside and the outside of the storage chamber is formed, and when (deaeration port area / exposed area of the titanium-based powder compact) is α, 0.0001 ≦ α ≦ 0.1 is set. It is characterized by having.

[Procedure amendment 9]

[Document name to be amended] Statement

[Correction target item name] 0012

[Correction method] Change

[Correction contents]

[0012] In the titanium sintering method according to the second invention, the heating is performed by heating.
Step and sintering a titanium-based powder compact comprising a heating step of heating in a heating furnace to titanium-based powder compact for sintering to prepare a titanium-based powder compact for discharging the gaseous emissions with In the heating step, (area of deaeration port /
When the surface area of the titanium-based powder compact (α) is α, the difference is 0.1.
Using refractory container provided with a degassing port set to 0001 ≦ α ≦ 0.1, while accommodating a titanium-based powder compact in the accommodating chamber of the refractory vessel, by sintering a titanium-based powder compact, Sintering
Gaseous emissions from the vent during reflow
It is characterized by discharging .

[Procedure amendment 10]

[Document name to be amended] Statement

[Correction target item name] 0013

[Correction method] Change

[Correction contents]

[0013] The refractory container for sintering titanium according to the third invention has a storage chamber for accommodating a titanium-based powder compact that discharges a gaseous emission material with heating, and the titanium-based powder compact is stored in the storage chamber. In the refractory container for sintering the titanium-based powder compact disposed in the heating furnace for sintering the titanium-based powder compact in the accommodated state, a deaeration port communicating between the inside and outside of the accommodation chamber is formed. And a closing valve for closing the deaeration port and opening the deaeration port as the pressure in the storage chamber increases.

[Procedure amendment 11]

[Document name to be amended] Statement

[Correction target item name] 0017

[Correction method] Change

[Correction contents]

[0017] The exposed area of the titanium-based powder compact, Chita
Means the area in which the powder -based compact is exposed to the storage chamber of the refractory container. Since the bottom surface of the titanium-based powder compact is placed in the refractory container, when the bottom surface of the titanium-based powder compact is not exposed to the accommodation room of the refractory container, the titanium-based powder compact for setting α is set. The exposed area of the body does not include the area of the bottom surface of the powder compact. According to engagement Ru titanium sintering method in the second invention, the steps of preparing a titanium-based powder compact,
And a heating step of heating the titanium-based powder compact in a heating furnace for sintering. The titanium-based powder compact is titanium
It is formed by molding a powder aggregate having a system powder as a main component. For example, a green compact obtained by compression-molding a powder aggregate can be employed.

[Procedure amendment 12]

[Document name to be amended] Statement

[Correction target item name] 0018

[Correction method] Change

[Correction contents]

As the powder, a titanium-based powder is used . One general, there is at least one form below the titanium-based powder compact. That is, a form in which a wax that can function as a lubricant for ensuring the smoothness of molding and the like is contained in the powder compact, and a binder such as an organic binder that enhances binding of powder particles is contained in the powder compact. There is a form and a form in which moisture adheres to the powder compact.

[Procedure amendment 13]

[Document name to be amended] Statement

[Correction target item name] 0021

[Correction method] Change

[Correction contents]

[0021] In titanium based powder compact, the thermal history during the heating, the powder, the type of wax, but also differs depending on the size of the powder compact, the process of discharging the like wax contained in the powder compact (e.g. 30 at 300-600 ° C
Minutes to 4 hours), and dehydrogenation treatment of the titanium hydride powder constituting the powder compact (for example, at 800 to 1100 ° C. for 3 hours).
0 minute to 3 hours) and a sintering process (for example, at 1200 to 1400 ° C. for 30 minutes to 10 hours) which means main sintering. However, the heating temperature and the heating time relating to the heat history are, of course, not limited thereto. As the heating furnace, a structure having a furnace wall of a carbon material or the like can be adopted.

[Procedure amendment 14]

[Document name to be amended] Statement

[Correction target item name] 0042

[Correction method] Change

[Correction contents]

In Test Example A1, a titanium-based powder compact was used as a test piece. The titanium-based powder compact is a green compact obtained by using a mixed material obtained by mixing a wax with a raw material powder containing titanium hydride powder (TiH ₂ powder) as a main component, and compressing the mixed material with a molding die. The titanium-based powder compact becomes a titanium-based sintered body by sintering. The amounts of oxygen and carbon contained in the titanium-based sintered body were measured, and are shown in Table 1. As shown in Table 1, in Test Example A1 according to the present invention, the amount of oxygen contained in the titanium-based sintered body was 0.30% by weight, and the amount of carbon was 0.055% by weight. Was. In this way test example A1, the amount of oxygen contained in the titanium-based sintered body and carbon content was significantly less.

[Procedure amendment 15]

[Document name to be amended] Statement

[Correction target item name] Fig. 8

[Correction method] Change

[Correction contents]

FIG. 8 is a graph showing the relationship between the amount of oxygen in a sintered body and α .

Claims (3)

[Claims] An apparatus for sintering a powder compact, which is provided in a heating furnace for sintering the powder compact in a state in which the powder compact is housed in the accommodation chamber, is provided. In the refractory container, a deaeration port communicating the inside and the outside of the storage chamber is formed, and when (aeration area / exposed area of the powder compact) is α, 0.0001 ≦ α ≦ 0. A refractory container for sintering powder compacts, which is set to 1. 2. A method for sintering a powder compact, comprising: a step of preparing a powder compact; and a heating step of heating the powder compact in a heating furnace for sintering. When the area of the deaeration port / the exposed area of the powder compact is α, a refractory container having a deaeration port set to 0.0001 ≦ α ≦ 0.1 is used, and the accommodation chamber of the refractory container is used. Sintering the powder compact in a state in which the powder compact is accommodated in the sintering method. 3. A sintering apparatus for sintering a powder compact which is provided in a heating furnace for sintering the powder compact while the powder compact is housed in the accommodation chamber. In the refractory container, a deaeration port communicating the inside and outside of the storage chamber is formed, and a closing valve for closing the deaeration port and opening the deaeration port with an increase in the pressure of the storage chamber is provided. A refractory container for sintering powder compacts, wherein